title: A labile pool of IQGAP1 disassembles endothelial adherens junctions.
abstract: Adhesion molecules are known to play an important role in endothelial activation and angiogenesis. Here we determined the functional role of IQGAP1 in the regulation of endothelial adherens junctions. VE-cadherin is found to be associated with actin filaments and thus stable, but IQGAP1 at intercellular junctions is not bound to actin filaments and thus labile. Expression of GFP labeled VE-α-catenin is shown to increase the electrical resistance across HUVEC monolayers and diminishes endogenous labile IQGAP1 at the intercellular junctions. Knockdown of endogenous IQGAP1 enhances intercellular adhesion in HUVECs by increasing the association of VE-cadherin with P120 and β-catenin. IQGAP1 knockdown also decreases the interaction of N-cadherin with P120 and β-catenin. Together, these results suggest that a labile pool of IQGAP1 at intercellular junctions disassembles adherens junctions and thus impairs endothelial cell-cell adhesion.
authors.affiliation: Department of Anesthesiology, 1st Affiliated Hospital, China Medical University, Shenyang 110001, Liaoning, China. went@scut.edu.cn.
authors.forename: Zhiguo
authors.initials: Z
authors.lastname: Yuan
authors.forename: Wentao
authors.initials: W
authors.lastname: Zhang
authors.forename: Wen
authors.initials: W
authors.lastname: Tan
mesh_terms: D022005:Adherens Junctions / Q000235:genetics / Q000378:metabolism*; D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism; D015820:Cadherins / Q000235:genetics / Q000378:metabolism; D002448:Cell Adhesion / Q000502:physiology; D061307:Human Umbilical Vein Endothelial Cells / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D051178:alpha Catenin / Q000235:genetics / Q000378:metabolism; D020703:ras GTPase-Activating Proteins / Q000235:genetics / Q000378:metabolism*; D000099152:Cadherin 5
chemical_list: D015703:Antigens, CD; D015820:Cadherins; D051178:alpha Catenin; D020703:ras GTPase-Activating Proteins; D000099152:Cadherin 5; C101203:IQ motif containing GTPase activating protein 1